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3 years ago

10

4 men or 12 boys can do a certain work in 36 days. How long will 6 men and 10 boys take to do it?

1 answer:

Aneli [31]3 years ago

6 0

Answer:

a week

Step-by-step explanation:

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How much in Federal taxes does Curtis pay annually?

Hunter-Best [27]

The amount of Federal Taxes that Curtis pays annually would be 1538.68.

8 0

3 years ago

You have been asked to design a can shaped like right circular cylinder that can hold a volume of 432π-cm3. What dimensions of t

rosijanka [135]

Answer:

$Height = 12cm$

$Radius = 6cm$

Step-by-step explanation:

Given

Represent volume with v, height with h and radius with r

$V = 432\pi$

Required

Determine the values of h and r that uses the least amount of material

Volume is calculated as:

$V = \pi r^2h\\$

Substitute 432π for V

$432\pi = \pi r^2h$

Divide through by π

$432 = r^2h$

Make h the subject:

$h = \frac{432}{r^2}$

Surface Area (A) of a cylinder is calculated as thus:

$A=2\pi rh+2\pi r^2$

Substitute $\frac{432}{r^2}$ for h in $A=2\pi rh+2\pi r^2$

$A=2\pi r(\frac{432}{r^2})+2\pi r^2$

$A=2\pi (\frac{432}{r})+2\pi r^2$

Factorize:

$A=2\pi (\frac{432}{r} + r^2)$

To minimize, we have to differentiate both sides and set $A' = 0$

$A'=2\pi (-\frac{432}{r^2} + 2r)$

Set $A' = 0$

$0=2\pi (-\frac{432}{r^2} + 2r)$

Divide through by $2\pi$

$0= -\frac{432}{r^2} + 2r$

$\frac{432}{r^2} = 2r$

Cross Multiply

$2r * r^2 = 432$

$2r^3 = 432$

Divide through by 2

$r^3 = 216$

Take cube roots of both sides

$r = \sqrt[3]{216}$

$r = 6$

Recall that:

$h = \frac{432}{r^2}$

$h = \frac{432}{6^2}$

$h = \frac{432}{36}$

$h = 12$

Hence, the dimension that requires the least amount of material is when

$Height = 12cm$

$Radius = 6cm$

3 0

3 years ago

True or false<br> The solution set of 2x+5=x-3is {-8}

irinina [24]

Answer:

True

Step-by-step explanation:

2x+5=x-3 is (-8)

This is the correct answer

3 0

3 years ago

Read 2 more answers

Which of the following, to the nearest tenth, is a solution of f(x) = g (x) if f (x) = in (x + 5 ) - 1 and g(x) =x^3 - 2x+1

Dovator [93]

Answer:

c

Step-by-step explanation:

5 0

3 years ago

Martin is cleaning the tires of his bicycle. He notices that his bicycle tire has a radius of 8 inches. How much bigger is the a

algol [13]

Strange question, as normally we would not calculate the "area of the tire." A tire has a cross-sectional area, true, but we don't know the outside radius of the tire when it's mounted on the wheel.

We could certainly calculate the area of a circle with radius 8 inches; it's

A = πr^2, or (here) A = π (8 in)^2 = 64π in^2.

The circumference of the wheel (of radius 8 in) is C = 2π*r, or 16π in.

The numerical difference between 64π and 16π is 48π; this makes no sense because we cannot compare area (in^2) to length (in).

If possible, discuss this situatio with your teacher.

8 0

3 years ago